A 15-year-old albino boy has been found dismembered in Burundi a week after going missing, the first such killing in the country in three years, a local albino group said Sunday.

Albinos, who have white skin and yellow hair as a result of a genetic disorder that causes the absence of pigmentation, are killed regularly in some African countries for their body parts, which are used in witchcraft rituals.

The teenager was found dead late Saturday in the northwest of the country along the Rusizi river separating Burundi from the DR Congo, not far from his home village.

"The young albino was killed atrociously... His murderers cut his right leg off at the knee, his right arm and his tongue," said Kassim Kazungu, the head of the local association Albinos Without Borders.

More than 20 albinos have been killed in Burundi since 2008, with the last case in 2016 when a five-year-old girl was found dismembered after being taken from her home.

Kazungu said a four-year-old albino boy had been missing since October 2018 from the village of Cendajuri near the Tanzanian border, but that he had "no hope" of finding him alive.

Some experts believe the demand for albino body parts in Tanzania -- where such attacks are the most prevalent -- has fuelled such killings in border areas.